Experimental Study of Combustible and Non-combustible Construction in a Natural Fire

With the adoption of performance-based fire design and the development of new engineered wood products, wood-based mid-rise and high-rise buildings are beginning to be constructed all around the globe. This trend has accelerated efforts to gain more understanding of the risks associated with combustible construction. To compare the differences between combustible and non-combustible construction, a series of full scale fire tests was conducted at Carleton University, the results of which are presented in this paper. These tests represented real bedroom fires with different room construction types: cross laminated timber (CLT) construction, light timber frame construction and light steel frame construction. Results showed that gypsum boards provided a better protection to CLT panels than to light frame walls. Compared with fires in the protected rooms, fire in the unprotected CLT room during the fully developed phase showed accelerated fire development and resulted in over 80% higher total heat release rate (THRR) but slightly lower room temperatures, and external burning contributed to about 64% of the THRR. It was also found that the light timber frame walls and light steel frame walls behaved very differently in the real fire. Furthermore, higher charring rates in both the unprotected CLT panels (1.0 mm/min) and wood studs (1.2 mm/min) were obtained in the real fire than those in the standard fire.